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  <div class="section" id="module-altgraph.Graph">
<span id="altgraph-graph-basic-directional-graphs"></span><h1><a class="reference internal" href="#module-altgraph.Graph" title="altgraph.Graph: Basic directional graphs."><tt class="xref py py-mod docutils literal"><span class="pre">altgraph.Graph</span></tt></a> &#8212; Basic directional graphs<a class="headerlink" href="#module-altgraph.Graph" title="Permalink to this headline">¶</a></h1>
<p>The module <a class="reference internal" href="#module-altgraph.Graph" title="altgraph.Graph: Basic directional graphs."><tt class="xref py py-mod docutils literal"><span class="pre">altgraph.Graph</span></tt></a> provides a class <a class="reference internal" href="#altgraph.Graph.Graph" title="altgraph.Graph.Graph"><tt class="xref py py-class docutils literal"><span class="pre">Graph</span></tt></a> that
represents a directed graph with <em>N</em> nodes and <em>E</em> edges.</p>
<dl class="class">
<dt id="altgraph.Graph.Graph">
<em class="property">class </em><tt class="descclassname">altgraph.Graph.</tt><tt class="descname">Graph</tt><big>(</big><span class="optional">[</span><em>edges</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph" title="Permalink to this definition">¶</a></dt>
<dd><p>Constructs a new empty <a class="reference internal" href="#altgraph.Graph.Graph" title="altgraph.Graph.Graph"><tt class="xref py py-class docutils literal"><span class="pre">Graph</span></tt></a> object. If the optional
<em>edges</em> parameter is supplied, updates the graph by adding the
specified edges.</p>
<p>All of the elements in <em>edges</em> should be tuples with two or three
elements. The first two elements of the tuple are the source and
destination node of the edge, the optional third element is the
edge data.  The source and destination nodes are added to the graph
when the aren&#8217;t already present.</p>
</dd></dl>

<div class="section" id="node-related-methods">
<h2>Node related methods<a class="headerlink" href="#node-related-methods" title="Permalink to this headline">¶</a></h2>
<dl class="method">
<dt id="altgraph.Graph.Graph.add_node">
<tt class="descclassname">Graph.</tt><tt class="descname">add_node</tt><big>(</big><em>node</em><span class="optional">[</span>, <em>node_data</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.add_node" title="Permalink to this definition">¶</a></dt>
<dd><p>Adds a new node to the graph if it is not already present. The new
node must be a hashable object.</p>
<p>Arbitrary data can be attached to the node via the optional <em>node_data</em>
argument.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">the node also won&#8217;t be added to the graph when it is
present but currently hidden.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.hide_node">
<tt class="descclassname">Graph.</tt><tt class="descname">hide_node</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.hide_node" title="Permalink to this definition">¶</a></dt>
<dd><p>Hides a <em>node</em> from the graph. The incoming and outgoing edges of
the node will also be hidden.</p>
<p>Raises <a class="reference internal" href="core.html#altgraph.GraphError" title="altgraph.GraphError"><tt class="xref py py-class docutils literal"><span class="pre">altgraph.GraphError</span></tt></a> when the node is not (visible)
node of the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.restore_node">
<tt class="descclassname">Graph.</tt><tt class="descname">restore_node</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.restore_node" title="Permalink to this definition">¶</a></dt>
<dd><p>Restores a previously hidden <em>node</em>. The incoming and outgoing
edges of the node are also restored.</p>
<p>Raises <a class="reference internal" href="core.html#altgraph.GraphError" title="altgraph.GraphError"><tt class="xref py py-class docutils literal"><span class="pre">altgraph.GraphError</span></tt></a> when the node is not a hidden
node of the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.restore_all_nodes">
<tt class="descclassname">Graph.</tt><tt class="descname">restore_all_nodes</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.restore_all_nodes" title="Permalink to this definition">¶</a></dt>
<dd><p>Restores all hidden nodes.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.number_of_nodes">
<tt class="descclassname">Graph.</tt><tt class="descname">number_of_nodes</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.number_of_nodes" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of visible nodes in the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.number_of_hidden_nodes">
<tt class="descclassname">Graph.</tt><tt class="descname">number_of_hidden_nodes</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.number_of_hidden_nodes" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of hidden nodes in the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.node_list">
<tt class="descclassname">Graph.</tt><tt class="descname">node_list</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.node_list" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a list with all visible nodes in the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.hidden_node_list">
<tt class="descclassname">Graph.</tt><tt class="descname">hidden_node_list</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.hidden_node_list" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a list with all hidden nodes in the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.node_data">
<tt class="descclassname">altgraph.Graph.</tt><tt class="descname">node_data</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.node_data" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the data associated with the <em>node</em> when it was
added.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.describe_node">
<tt class="descclassname">Graph.</tt><tt class="descname">describe_node</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.describe_node" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <em>node</em>, the node&#8217;s data and the lists of outgoing
and incoming edges for the node.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">the edge lists should not be modified, doing so
can result in unpredicatable behavior.</p>
</div>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.__contains__">
<tt class="descclassname">Graph.</tt><tt class="descname">__contains__</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.__contains__" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns True iff <em>node</em> is a node in the graph. This
method is accessed through the <em>in</em> operator.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.__iter__">
<tt class="descclassname">Graph.</tt><tt class="descname">__iter__</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.__iter__" title="Permalink to this definition">¶</a></dt>
<dd><p>Yield all nodes in the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.out_edges">
<tt class="descclassname">Graph.</tt><tt class="descname">out_edges</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.out_edges" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the list of outgoing edges for <em>node</em></p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.inc_edges">
<tt class="descclassname">Graph.</tt><tt class="descname">inc_edges</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.inc_edges" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the list of incoming edges for <em>node</em></p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.all_edges">
<tt class="descclassname">Graph.</tt><tt class="descname">all_edges</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.all_edges" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the list of incoming and outgoing edges for <em>node</em></p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.out_degree">
<tt class="descclassname">Graph.</tt><tt class="descname">out_degree</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.out_degree" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of outgoing edges for <em>node</em>.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.inc_degree">
<tt class="descclassname">Graph.</tt><tt class="descname">inc_degree</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.inc_degree" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of incoming edges for <em>node</em>.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.all_degree">
<tt class="descclassname">Graph.</tt><tt class="descname">all_degree</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.all_degree" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of edges (incoming or outgoing) for <em>node</em>.</p>
</dd></dl>

</div>
<div class="section" id="edge-related-methods">
<h2>Edge related methods<a class="headerlink" href="#edge-related-methods" title="Permalink to this headline">¶</a></h2>
<dl class="method">
<dt id="altgraph.Graph.Graph.add_edge">
<tt class="descclassname">Graph.</tt><tt class="descname">add_edge</tt><big>(</big><em>head_id</em>, <em>tail_id</em><span class="optional">[</span>, <em>edge data</em><span class="optional">[</span>, <em>create_nodes</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.add_edge" title="Permalink to this definition">¶</a></dt>
<dd><p>Adds a directed edge from <em>head_id</em> to <em>tail_id</em>. Arbitrary data can
be added via <em>edge_data</em>.  When <em>create_nodes</em> is <em>True</em> (the default),
<em>head_id</em> and <em>tail_id</em> will be added to the graph when the aren&#8217;t
already present.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.hide_edge">
<tt class="descclassname">Graph.</tt><tt class="descname">hide_edge</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.hide_edge" title="Permalink to this definition">¶</a></dt>
<dd><p>Hides an edge from the graph. The edge may be unhidden at some later
time.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.restore_edge">
<tt class="descclassname">Graph.</tt><tt class="descname">restore_edge</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.restore_edge" title="Permalink to this definition">¶</a></dt>
<dd><p>Restores a previously hidden <em>edge</em>.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.restore_all_edges">
<tt class="descclassname">Graph.</tt><tt class="descname">restore_all_edges</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.restore_all_edges" title="Permalink to this definition">¶</a></dt>
<dd><p>Restore all edges that were hidden before, except for edges
referring to hidden nodes.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.edge_by_node">
<tt class="descclassname">Graph.</tt><tt class="descname">edge_by_node</tt><big>(</big><em>head</em>, <em>tail</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.edge_by_node" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the edge ID for an edge from <em>head</em> to <em>tail</em>,
or <a class="reference external" href="http://docs.python.org/library/constants.html#None" title="(in Python v2.7)"><tt class="xref py py-data docutils literal"><span class="pre">None</span></tt></a> when no such edge exists.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.edge_by_id">
<tt class="descclassname">Graph.</tt><tt class="descname">edge_by_id</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.edge_by_id" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the head and tail of the <em>edge</em></p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.edge_data">
<tt class="descclassname">Graph.</tt><tt class="descname">edge_data</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.edge_data" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the data associated with the <em>edge</em>.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.head">
<tt class="descclassname">Graph.</tt><tt class="descname">head</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.head" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the head of an <em>edge</em></p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.tail">
<tt class="descclassname">Graph.</tt><tt class="descname">tail</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.tail" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the tail of an <em>edge</em></p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.describe_edge">
<tt class="descclassname">Graph.</tt><tt class="descname">describe_edge</tt><big>(</big><em>edge</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.describe_edge" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the <em>edge</em>, the associated data, its head and tail.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.number_of_edges">
<tt class="descclassname">Graph.</tt><tt class="descname">number_of_edges</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.number_of_edges" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of visible edges.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.number_of_hidden_edges">
<tt class="descclassname">Graph.</tt><tt class="descname">number_of_hidden_edges</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.number_of_hidden_edges" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the number of hidden edges.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.edge_list">
<tt class="descclassname">Graph.</tt><tt class="descname">edge_list</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.edge_list" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a list with all visible edges in the graph.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.hidden_edge_list">
<tt class="descclassname">Graph.</tt><tt class="descname">hidden_edge_list</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.hidden_edge_list" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a list with all hidden edges in the graph.</p>
</dd></dl>

</div>
<div class="section" id="graph-traversal">
<h2>Graph traversal<a class="headerlink" href="#graph-traversal" title="Permalink to this headline">¶</a></h2>
<dl class="method">
<dt id="altgraph.Graph.Graph.out_nbrs">
<tt class="descclassname">Graph.</tt><tt class="descname">out_nbrs</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.out_nbrs" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a list of all nodes connected by outgoing edges.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.inc_nbrs">
<tt class="descclassname">Graph.</tt><tt class="descname">inc_nbrs</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.inc_nbrs" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a list of all nodes connected by incoming edges.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.all_nbrs">
<tt class="descclassname">Graph.</tt><tt class="descname">all_nbrs</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.all_nbrs" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a list of nodes connected by an incoming or outgoing edge.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.forw_topo_sort">
<tt class="descclassname">Graph.</tt><tt class="descname">forw_topo_sort</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.forw_topo_sort" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a list of nodes where the successors (based on outgoing
edges) of any given node apear in the sequence after that node.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.back_topo_sort">
<tt class="descclassname">Graph.</tt><tt class="descname">back_topo_sort</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.back_topo_sort" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a list of nodes where the successors (based on incoming
edges) of any given node apear in the sequence after that node.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.forw_bfs_subgraph">
<tt class="descclassname">Graph.</tt><tt class="descname">forw_bfs_subgraph</tt><big>(</big><em>start_id</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.forw_bfs_subgraph" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a subgraph consisting of the breadth first
reachable nodes from <em>start_id</em> based on their outgoing edges.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.back_bfs_subgraph">
<tt class="descclassname">Graph.</tt><tt class="descname">back_bfs_subgraph</tt><big>(</big><em>start_id</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.back_bfs_subgraph" title="Permalink to this definition">¶</a></dt>
<dd><p>Return a subgraph consisting of the breadth first
reachable nodes from <em>start_id</em> based on their incoming edges.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.iterdfs">
<tt class="descclassname">Graph.</tt><tt class="descname">iterdfs</tt><big>(</big><em>start</em><span class="optional">[</span>, <em>end</em><span class="optional">[</span>, <em>forward</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.iterdfs" title="Permalink to this definition">¶</a></dt>
<dd><p>Yield nodes in a depth first traversal starting at the <em>start</em>
node.</p>
<p>If <em>end</em> is specified traversal stops when reaching that node.</p>
<p>If forward is True (the default) edges are traversed in forward
direction, otherwise they are traversed in reverse direction.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.iterdata">
<tt class="descclassname">Graph.</tt><tt class="descname">iterdata</tt><big>(</big><em>start</em><span class="optional">[</span>, <em>end</em><span class="optional">[</span>, <em>forward</em><span class="optional">[</span>, <em>condition</em><span class="optional">]</span><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.iterdata" title="Permalink to this definition">¶</a></dt>
<dd><p>Yield the associated data for nodes in a depth first traversal
starting at the <em>start</em> node. This method will not yield values for nodes
without associated data.</p>
<p>If <em>end</em> is specified traversal stops when reaching that node.</p>
<p>If <em>condition</em> is specified and the condition callable returns
False for the associated data this method will not yield the
associated data and will not follow the edges for the node.</p>
<p>If forward is True (the default) edges are traversed in forward
direction, otherwise they are traversed in reverse direction.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.forw_bfs">
<tt class="descclassname">Graph.</tt><tt class="descname">forw_bfs</tt><big>(</big><em>start</em><span class="optional">[</span>, <em>end</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.forw_bfs" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a list of nodes starting at <em>start</em> in some bread first
search order (following outgoing edges).</p>
<p>When <em>end</em> is specified iteration stops at that node.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.back_bfs">
<tt class="descclassname">Graph.</tt><tt class="descname">back_bfs</tt><big>(</big><em>start</em><span class="optional">[</span>, <em>end</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.back_bfs" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a list of nodes starting at <em>start</em> in some bread first
search order (following incoming edges).</p>
<p>When <em>end</em> is specified iteration stops at that node.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.get_hops">
<tt class="descclassname">Graph.</tt><tt class="descname">get_hops</tt><big>(</big><em>start</em><span class="optional">[</span>, <em>end</em><span class="optional">[</span>, <em>forward</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.get_hops" title="Permalink to this definition">¶</a></dt>
<dd><p>Computes the hop distance to all nodes centered around a specified node.</p>
<p>First order neighbours are at hop 1, their neigbours are at hop 2 etc.
Uses <a class="reference internal" href="#altgraph.Graph.Graph.forw_bfs" title="altgraph.Graph.Graph.forw_bfs"><tt class="xref py py-meth docutils literal"><span class="pre">forw_bfs()</span></tt></a> or <a class="reference internal" href="#altgraph.Graph.Graph.back_bfs" title="altgraph.Graph.Graph.back_bfs"><tt class="xref py py-meth docutils literal"><span class="pre">back_bfs()</span></tt></a> depending on the value of
the forward parameter.</p>
<p>If the distance between all neighbouring nodes is 1 the hop number
corresponds to the shortest distance between the nodes.</p>
<p>Typical usage:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">&gt;&gt;&gt; </span><span class="k">print</span> <span class="n">graph</span><span class="o">.</span><span class="n">get_hops</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">8</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="p">[(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">),</span> <span class="p">(</span><span class="mi">2</span><span class="p">,</span> <span class="mi">1</span><span class="p">),</span> <span class="p">(</span><span class="mi">3</span><span class="p">,</span> <span class="mi">1</span><span class="p">),</span> <span class="p">(</span><span class="mi">4</span><span class="p">,</span> <span class="mi">2</span><span class="p">),</span> <span class="p">(</span><span class="mi">5</span><span class="p">,</span> <span class="mi">3</span><span class="p">),</span> <span class="p">(</span><span class="mi">7</span><span class="p">,</span> <span class="mi">4</span><span class="p">),</span> <span class="p">(</span><span class="mi">8</span><span class="p">,</span> <span class="mi">5</span><span class="p">)]</span>
<span class="go"># node 1 is at 0 hops</span>
<span class="go"># node 2 is at 1 hop</span>
<span class="go"># ...</span>
<span class="go"># node 8 is at 5 hops</span>
</pre></div>
</div>
</dd></dl>

</div>
<div class="section" id="graph-statistics">
<h2>Graph statistics<a class="headerlink" href="#graph-statistics" title="Permalink to this headline">¶</a></h2>
<dl class="method">
<dt id="altgraph.Graph.Graph.connected">
<tt class="descclassname">Graph.</tt><tt class="descname">connected</tt><big>(</big><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.connected" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns True iff every node in the graph can be reached from
every other node.</p>
</dd></dl>

<dl class="method">
<dt id="altgraph.Graph.Graph.clust_coef">
<tt class="descclassname">Graph.</tt><tt class="descname">clust_coef</tt><big>(</big><em>node</em><big>)</big><a class="headerlink" href="#altgraph.Graph.Graph.clust_coef" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns the local clustering coefficient of node.</p>
<p>The local cluster coefficient is the proportion of the actual number
of edges between neighbours of node and the maximum number of
edges between those nodes.</p>
</dd></dl>

</div>
</div>


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